Tetrakisazo dyestuffs



United States Patent 2,917,504 TETRAKISAZO DYESTUFFS Klaus Biickmann; Koln-Stammheim, Germany,

to Farbenfabriken Bayer Aktiengesellschaft, kusen, Germany, a corporation of Germany No Drawing. Application August 4, 1955 Serial No. 526,553

Claims priority, application Germany August 25; 1954- 6 Claims. (Cl- 260-167) assignor Lever- The present invention relates to tetrakisazo dyestuffs and to a process of making the same; more particularly, it relates to dyestufls corresponding to the general for- In this formula, R stands for hydrogen, lower alkyl, hydroxy lower alkyl or aryl and R and R mean a radical of the benzene or naphthalene series, at least one of the radicals R and R hearing at least one sulfonic acid group, and R stands for a radical of the benzene series carrying the N H-C-NHR- group in o-position to the azo bridge and the -NH-group in p-position to the azo bridge.

The new tetrakisazo dyestuffs can be obtained by coupling diazotized amino monoazo dyestufis of the hen zene or naphthalene series with a 3-amino-1-phenyl urea of the general formula:

wherein R has the same meaning as above and the henzene nucleus A may be further substituted except for the coupling position and converting the aminodisazo dyestuffs thus obtained-cg. by treating them with phosgeneinto their ureas.

The 3-amino-phenyl ureas used as coupling components can be obtained by reacting 1-amino-3-acylamino-ben- I zenes with chloro-formic acid phenyl ester in aqueous acetic solution, treating the urethane thus obtained with ammonia or an amine in neutral to alkaline medium. The 3-acylamino-1-phenyl urea, which is formed while phenol is split off, is hydrolised in acid'solutionto'form 3-amino-l-phenyl urea.

The new tetrakisazo dyestufis dye cotton and regenerated cellulose essentially orange-red to reddish brown shades of very good fastness to light and improved dischargeability.

' in red-brown shades of The following examples illustrate the invention without, however; limiting it thereto; the parts being by weight:

Example 1 357 parts of 4-amino-azo-benzene-3,4'-disulfonic acid are diazotized in usual manner and coupled with 151 parts of S-amino-phenyl urea in acetic acid solution. The resulting amino-disazo dyestufl is converted into the corresponding urea by reacting it with phosgene. When the 7 amino disazo'dyestuff has completely reacted, the resulting tetrakisazo dyestufi of the formula:

2 is filtered and dried. It represents a brown powder which is readily soluble in water. The new dyestufi dyes cotton and regenerated cellulose in orange-red shades of very good fastness to light and very good dischargeability.

Example 2 357 parts of 4-amino-azo-benzene-3,4-sulfonic acid are diazotized as described in Example 1 and then combined with parts of N-(3-amino)-1-phenyl-N-hydroxyethyl urea. into its urea with phosgene. azo dyestufi corresponding to After drying the resulting the formula:

BOrH NEG-fil-NH-CHr-CHa-OH is a brownish red powder which is readily soluble in water; it dyes cotton and regenerated cellulose in scarlet red shades of very good fastness to light and good dischargeability. 4

Example 3 The amino azo dyestulf which can be obtained by coupling 253 parts of diazotized 1-aminobenzene-2,4-disulfonic acid and 121 parts of 1-amino-2,5-dimethylbenzene is -diazotized in usual manner and combined with v 151 parts of 3-amino-phenyl-urea in acetic acid solution. The formed amino disazo dyestuif is converted into the urea with phospgene. The dyestufl thus obtained corresponds to the formula:

Ice Patented Dec. 15, 1959.

The formed amino disazo dyestulf is converted represents-a brownpowder which is soluble in water; it

dyes cotton and regenerated cellulose in orange-red shades of good fastness to light and good dischargeability.

Example, 5

The. monoazo dyestufi obtained by coupling-303 :parts 1 of diazotized 2-amino-naphthalene-6,8-disulfonic acid with:

107 parts of 1-arnino-3imethylbenzene is diazotized in usual manner and coupled with151lp arts of 3.-aminophenyl ureain acetic acid solution. After converting;.the amino dyestuif'into the urea withflphosgene the tetrakisazo dyestuif of the formula:

is isolated and dried. It represents a brown powderwhich' is readily soluble in water; it dyes cotton ,and re generatedcellulose in brown shades of'good'ifastness to light and good ,dischargeability.

Example 6 The amino azo dyestuffs, obtained by coupling 253 parts of diazotized l-arninobenzene 2,5-disulfonic acid with 121 parts of 1-amino-2,5edimethylbenzene, is di'azotized in acetic acid solution and combined with 165'iparts of 3-arnino-4-methyl-l-phenyl'urea. The formed amino disazo dyestuif is converted into'the urea, with phfosgene.

After drying the resulting-lazo dyestufi of the general formula:

represents a .brown powder which is solublerin -water; it

dyes cotton and. regenerated cellulose in reddish-brown shades of good fastness to light and good-dischargeability;

" V smH.

. 4, We claim:

1. Tetrakisazo dyestuffscorresponding to the formula- 22 A- dyestulf according to claim l wherein the sulfonic' acid groups are attached to the R nucleus.

3. The tetrakisazo dyestuff corresponding to the following formula:

S 0 3H C H: C H! T l :H CH:

4. The tctrakisazo dyestufi corresponding to the fol lowing formula:

5. Thcitetrakisazo dyestuffcorresponding to the following formula:

6. The tetrakisazo dyestuficorresponding to the following formula:

SOiH- 1.

References Cited in the filelof this patent UNITED STATES PATENTS 1,863,792 Hentrich et al June 21, 1932 2,249,334 Sparks et al. July 15,1941 2,286,795 Dickey et al. June;16, 1942 2,606,897 Grandjean Aug. 12, 1952 2,708,668 Suckfull- May 17, 1955 

1. TETRAKISAZO DYESTUFFS CORRESPONDING TO THE FORMULA 